鹿蹄橐吾多糖LW_(21)的分离纯化及其结构分析  

Isolation,Purification and Structural Analysis of Water-Soluble Polysaccharide LW_(21) from Ligularia hodgsonii

作　　者：刘春兰[1] 杜宁[1] 徐桂云[2] 黄潇[1] 阿西娜[1] 

机构地区：[1]中央民族大学生命与环境科学学院,北京100081 [2]中国科学院化学研究所,北京100080

出　　处：《食品科学》2012年第11期57-61,共5页Food Science

基　　金：中央高校基本科研业务费专项资金资助项目(0910KYZY44);"111创新引智计划"工程项目(B08044);中央民族大学"985"工程项目(MUC985-9)

摘　　要：目的:确定鹿蹄橐吾多糖LW21的结构,为探讨鹿蹄橐吾多糖的药理活性,合理利用鹿蹄橐吾这种植物资源提供依据。方法:水提取醇沉获得鹿蹄橐吾水溶性粗多糖LW,经酸性乙醇分级和DEAE-SephdexA-25纯化得多糖LW21。纸层析、醋酸纤维薄膜电泳和Sepharose CL-4B柱层析进行纯度鉴定,LW21结构分析采用高碘酸氧化、Smith降解、甲基化分析及IR、NMR、GC和GC-MS等方法。结果表明:LW21为均一多糖,相对分子质量约为1.1×106。其单糖组成为鼠李糖(Rha)、阿拉伯糖(Ara)、甘露糖(Man)、葡萄糖(Glc)、半乳糖(Gal),物质的量比为7.4:11.9:25.7:40.0:14.9。多糖LW21为有分枝结构,主链由Glc和Man构成,其中其中Man主要以β(1→2)和β(1→6)糖苷键连接,β(1→2)糖苷键在3-O处和6-O处有分枝,β(1→6)糖苷键在2-O和4-O处有分枝,Glc也主要以β(1→2)及β(1→6)糖苷键连接,β(1→2)糖苷键在6-O处有分枝,β(1→6)糖苷键连接,在2-O处有分枝。分子支链由Ara、Rha、Gal构成。末端残基为Gal、Ara、Rha、Glc。结论:鹿蹄橐吾多糖LW2 1是一新结构多糖,为首次从鹿蹄橐吾中分离得到。Objective： to isaolate, purify and structurally characterize a water-soluble polysaccharide from the whole herbs of Ligularia hodgsonii. Methods： crude polysaccharide named as LW was extracted from Ligularia hodgsonii. A ploysaccharide fraction named as LW21 was obtained after acidic ethanol fractionation and DEAE-Sephadex A-25 gel filtration. The purity of LW21 was identified by paper chromatography, Sepharose CL-4B chromatography and cellulous acetate electrophoresis, and its structure was analyzed by HIO4 oxidation, Smith degradation, methylation, IR, NMR, GC and GC-MS. Results： LW21 was a homogenous polysaccharide. LW21 was composed of rhamose （Rha）, arabinose （Ara）, mannose （Man）, glucose （Glc） and galactose （Gal） with a molar ratio of 7.4：11.9： 25.7： 40.0： 14.9. Its average molecular weight was 110 kD. Its main chain was made up of β -（1→2）-linked or β-（1→6）-linked Man, and β -（1 →2）-linked or β-（1 → 6）-linked Glc residues. The β -（1→2）-linked Man was substituted at 2 - O and 4 - O; β -（1→6）-linked Man was substituted at 3 - O and 6 - O; and β -（1→2）-linked Glc was substituted at 6 - O;β -（1→6）-linked Gal was substituted at 2 - O. The side chain was composed of Rha, Ara and Gal. The non-reduced end was composed of Gal, Ara, Rha and Glc. Conclusion： LW21 is a new polysaccharide isolated from Ligularia hodgsonii for the first time.

关 键 词：鹿蹄橐吾 多糖 甲基化分析 结构分析 

分 类 号：Q629[生物学—生物物理学]